Method of and apparatus for automatically stopping automatic presses



Nov. 18, 1924. 1,515,774

L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATICPRESSES Filed Sent. 14 1921 6 Sheets-Sheet l VENTOR A. L. ONE-5 Arm/M578WITNESSES Nov. 18, 1924. 1,515,774

1.. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPINGAUTOMATIC PHESSBS Filed Sent. 14 1921 6 Sheets-Sheet 2 INVENTOR L. L,Jon/5.5

fllwuj A TTORNEYS L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLYSTOPPING AUTOMATIC FRESSES Filed Sent. 14 192; 6 Sheets-Sheet 3 INVENTORAll .dozvas,

/ TNESSE A ITO/HIE Y8 Nov. 18, 1924. 1,515,774

L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATICPRESSES v Filed Sent. 14 192 6 Sheets-Sheet 4 v K\\\ l WITNESSES I ENTOR I, L.L ONES A TTOR/VEYS Nov. 18, 1 1,515,774

' L. L. JQNES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPKNGAUTOMATIC PRESSES Filed Sent. 14 N12 6 Sheets-Sheet 5 WITNESSESlM/E/VTO}? 7/4. 1, arm 56 i 4 a t C A TTOHNEYS Nov. 18, '1924.1,515.774'

L. L. JONES METHOD OF AND APPARATUS FOR AUTOMATICALLY STOPPING AUTOMATICPRESSES Filed Sent. 14 1921 6 Sheets-Slgetfi 4&9 74

INVENTOR WITNESSES 11.4 .JON

Patented Nov. 18, 1

UNITED STATES; PATENT OFFICE.

LYMAN LLEWELLYNJ'ONBS 0F SEATTLE. WASHINGTON.

METHOD OF AND APPA Application filed September 14, 1921.

To 1111' whom 51- may 3c it known that concern:

LYMA N; LLE pLLYN JONES, it citizen of Canada, and "ti resident ofSeattle, in the county of King' and stete of \Vashington,

have invented certain new :mzl useful improvements in "Metho'd s' of andApparatus for AutomaticaHy'Stopping Automatic Presses, of

is a specification.

which the following My invention relates to improvements in stop-motionmechanism, only in the construction,

ib d endjfdm ed,

arrangement herein but also in the meth the operation thereof;

and it consists not q etwni n 0d oil accomplishing vention is to providemeans i r, eutqmetrcally stopping an automat c "or, c'ptl i e r type ofpress for stumping tin ;c

the happening a like, upon of 21 number or false o anf e. :cess1\ -ely'thick ging of the can top" of thescrap chute'.

ler'idjtheifz esm g If" A further and most, import rr tobje'ct pi theinvention j is, to provid mally;

til a strain beyond a as described, in [the] operet'v e, is imposed onthe pressthrough i t slse 4' e es-Lees pre e rmined tioning, wherebythe, starting le iger l s dfi lflefll a single operatorican of suchpresses.

Other objects and pear in the ence being had to the ings, in whicli:

, ,oi Ln-" L nirention is to f' l command 7 a --number advantages 3pfollowin s ecificati'on refer- D r 7 r accompanying, draw} Figure l is aperspective zie vofengulines, illustrating invention in heavier press.light 6'11t' 'o'f, the lines,

Figure 2 is a similar vie'w f of thzit por- Lion-of the pressvindicated'ibyjtliei arrow,,a

in Figure 1,

Figure 3 is a vertical section of the-tin strip contact which strips fedFig. 3 structure in Fig. 3.

Figures 4, 5 and 6 parts of the tin -strip gauges the size of. tin intothe machine,

is a detail plan-mew, o f the are CIELAILVIEWS of contact disassembled,

sticking; of the die-.in thfe' ifiblk; t li i c liig RATUS FORAUTOMATICALLY STOPPING AUTOMATIC PRESSES.

Serial no; 500,717.

Figure 7 is a cross section, taken substantiallypn the line 77 ofFigured, illustrating 'the, construction of one of the junctionblocks,.'

"Figure 8 is a perspective View of the can lid discharge chute of thepress, also illustrating the disk by means of which the lid edges arecurled, r

a Figure!) is a cross section on the line 9-9 of Figure 8, illustratingthe construction ofthe kniie-ed e contact foriclosiiig anelectrical'cir'cuit en theflli'ds jam in the chute,

Figure IO 'is 'zi perspective"view oi the tin lscrap'l discharge chutealso shown at the righpnf Figure 2) i l l i is triiting the posi} t i'oirpf the' 'elec' eircnitminei fme' 1 tii of the totem Ti r m s'ii nis idireti ng i fi ms;-

li-l DIL. r h u 2 nd l figur 83se wire rf ileeip r fi; irbfl qo i; t spnesepo e ili'gimdeof operates and he li t me ,e ds 396? ipp rat ns f hinvent oni'rxiey jkrio i' i'i'. The, press coinpris'e's at frame 1',niith e. rack 2 Ioii which the tir'ifstr'ipssT arepile d, in. readinessto bcl"laced on' the'shelfor ledge 3, as shown in. g refl this shelf orledge; single sheets of tir'riiripicked up by's'uction cups 4, fed l t'h l' e wi I'eege iw '.(F 7 of the pressend-"th'en to "the righrioeijthedie 5 ,(see Fig; l0) t-o be z ctedon by the punch or,]dol1y'6,'see Figsfl and 2), and: thus fproduoe tin cen ,tops 15, two of which areshown thefdischarge chute 7 in Figure 8.' The mechanism by which the tinsheets are fed intothe press includes pusherfrods 4 (Fig. 2) which hareheads 4 fitted with glen-011549 to properly enga'gef the slieets'for thepurpose stated. The scrap tin is carried away by the scrap chute Lit)lit)

8 (see Fig. 1.) into which tlie'metal is kicked by the properly timedimpeller 9, shown in Figure 2. The construction of the scrap chute 8includes the opposed angle irons S which provide a supporting frame workfor the chute proper 8"; (Fig. 1'). Situated at the left and rightrespectively of the chute (Fig. 10) are members 8 and 8 for functioningto properly guide the scrap 10 until the chute portion 8 is reached.

The press is subject to a number of maloperations, which the inventionis designed to remedy to the extent of promptly stopping the press sothat the cause of such operation may be removed. Such causes are theintroduction into the machine of two plates T or of an excessively thickplate, sticking of the metal on the die 5 due to improper sharpening ofthe latter, clogging of the chute 7 by can tops, and clogging of thechute 8 by pieces of scrap metal.

The tin strip contact 10 comprises a plunger with a ball-end 11,normally pressed down by the spring 12 (see Fig. 3) so that a sheet oftinT must be forced into position therebeneath after having been pickedup by the suction cups 4 in Figure 2. A tin plate of normal thicknesssimply raises the plunger 10 without bringing the contacts 13 and 14into engagement, but when a plate of unusual thickness (see dotted linesig. 3) or two plates are forced under the ball 11, the contacts 13 and14 will then .be brought into engagement and short-circuit theelectro-magnet 15 (Fig. 1) which in turn release the lever 16 sothatth'e press is stopped. The lever 16 falls by gravity against therubber cushion 17.

It is necessary to understand the electrical circuit which embraces theelectro-magnets 15, and which is affected by the closure of the contacts13 and 14. A suitable source G furnishes electrical current, one wire 18being grounded to the frame 1 of the press, another wire 19 running tothe binding screw 20 of a metal ring 21 on one of two junction blocks. Alamp L is connected in the wire 19 for the purpose of providing aresistance. A wire 22 runs from the binding posts 23 on the junctionring 21, to one of the binding posts 24 of the electro-magnets 15 (seeFig. 16) the other binding post being grounded to the iron base 25, andso to the frame of the press as indicated in Figure 1.

Under normal conditions, i. e. the proper operation of the press,current flows from the source G, through lamp L over wire 19, junctionring 21, magnets 15 to ground at the frame, returning therefrom overwire 18 to the source G. The resultant energization of theelectro-magnets 15- is sufiiciently strong to maintain the attraction ofthe starting lever 16 through the normal jarring of the press due to theoperation thereof.

An abnormal jar \villshake the lever 16 loose so that it falls and stopsthe machine.

The closure of the contacts 13 and 14 (described above). short circuitsthe electromagnets 15 with the same result, current then flowing alonthe following path: From the source ir over wire 19 to the bindingpost20 and ring 21 of the first junction block, out at binding post 26,over wire 27 through the binding post 28 of the metal ri 29 of thesecond junction block, out at bin ing post 30, over wire 31 to thecontacts 14, from thence to the contact 13 (now in engagement) and backto the negative pole of the source G through the ground connections andwire 18.

The tin strip contact comprises a metal bushing 32 with threads at thebottom and a non-circular head by means of which the bushing is screwedinto a suitable opening in the press frame. This bushing has internalbores of several sizes; the bore 33, which accommodates the plunger 10,is tapered, the bore 34 is larger than the latter, and the bore 35 isthreaded to receive the insulating plug 36. An opening 37, communicatingwith the bore 34, reveals the contacts 13 and 14. A contact screw 38,occupying a threaded bore in the bushing 36, carries the contact 14which in turn is aflixed' to a' spring'38 in a bore of the screw 38. Thespring is held in place by a plug 39 through which the connection of thewire 31 tothetin strip contact is made. The insulating bushing or pin 36has kerfs at quarters. (see Fig. 5) so 5m upon screwing the pin downinto the bushing 32, the adjustment of the contact screw 38 becomesfixed.

The can top contact 41 consits of a piece of metal bent into L-shape andhaving the lowermost edge (Fi s. 8 and 9) sharpened so as to cut throngthe enamel or other covering on the can top and complete an electricalcircuit, in the event that one or more of such can tops ride on top ofothers and thus clog the chute 7 The electrical circuit mentioned, maybe traced in Figure 1: Gurrent flows from the source G over wire 19,junction ring 21 and wire 27.to the second junction ring 29, out at thebinding post 42, over Wire 43 to the knife edge contact 41, through themetal of the can top to ground at the frame of the press, thencereturning to the source Gr via wire 18.

The completion of this circuit again results in short circuiting theelectro-magnets 15 so that the latter lose strength and are comelled torelease the lever 16 so that the press is stopped. The connection of thewire 43 is made directly to the contact 41 as shown in Figure 8. Thiscontact is supported by a bracket 44, and the latter in turn by the sideof the chute 7. A block of insulation 45 separates the contact from thebracket.

Although the description immediately following has no direct bearing onthe invention itself, it may not be out of place to say that the cantops from the chute 7 are discharged into the semi-circularwthroat 46wherein the edges are curled by'comin in contact with the groove-edgedcurler-w eel 47. The can'tops sometimes clognat the mouth of the throat46 before being engaged by the curler wheel 47, and under such cir-.

cumstances, it :is necessary to stop the press. This is accomplishedthrough the function of the knife-edge contact 41 and in the manner justdisclosed i The scrap-chute contact 48 is much on the order of thecontact/41- just described, the exception/being :that the knife edge ofthe latter is now mitted, and thecontact is turned up instead of down.=/Ihe :contact 48 has a beveled approach 49. It is mounted beneath thescrap chute- 8 *(seeFig; 10) aninsulating block lroweverriintervening.It is only'whenthe chuteii8'abecomes clogged by anaccumuiationwofvscra'p. =t1n, that the contact 48 functions-21m:stopithe press, this being accomplished by: short .cir cuiting theelectro-magnets 15, current flowing along 'thefollowing patli:;-,-Erom.-the source Gover wire l9 to 'theiijunction ring 21, out at the bindingpost 51, ovenwire 52, to the contact 48, returning tozthei negativepole'of the source ofenergy-Wia thegronnd connection 'and wire"* 18.-*As? before, the elcctro-magnets 15 areshort circuited, caus: ing therelease of the leveril61and -the consequent stopping ofthe press. 5 4The lever-.16 has a connection 53 which-extends to: the means(not-shown) by which: the press is stopped.

The edge or the contact 48-(Fig. 10) does not reach high enough to makecontact with the scrap so long as it lays flat in the trough above it,and does not .become jammed. But the scrap is so light from having endscut out of it, that if it happens to catch in the chute it wads up sothat the impeller 9 (Fig 2) pushes the scrap down against the contactedge 48. The normal function of the impeller is to kick the scrap out ofthe chute.

It sometimes happens that the scrap chute is not adjusted properly,permitting the scrap to get underneath the chute. In such event, itstrikes the beveled approach 49 which, again, short circuits the currentand stops the press. It may also happen that the stripper-ring on thepunch of the press may push jammed scrap against the contact. In anyevent, the tendency of the scrap to jam in the chute soon causes asuflicicnt piling or doubling up of the scrap between the two pieces ofangle iron of which the chute is composed, thereupon making contact withthe member 48 and performing the function mentioned.

The bearing bracket 54 (Fig' 1) supports the outer end of the startinglever shaft 55 (Fig. 14) the reduced end of which moves freely in it. Itis important that the stopping lever 16 should have very little frictionat the moment when it is disengaged from the magnet 15. To further thispurpose, the frame 1 has an aperture at the right side madesuflicientlylarge to avoid contact with the starting-lever shaft 55. The leftreduced endof the shaft 55 has bearing in the left side of the frame.The lever 16 is fixed on the shaft The bracket 54-is. secured by meansof a screw 56 and dowels 57. It is desirable that the starting' rlevershaft should be loose enough in its bearing to allow a rolling motionand thereby vfacilitate the movement .of the leverupondeenergization ofthe magnet.

-.Both electric 'unction blocks are alike in construction. ne is shownin detail in Figure The junction ring 21 (mentioned before) issecuredon. the thick insulating washer 58 by the four binding screws. "Thiswasher is fitted-against a larger but thinner insulatingwasher59, allbeing held in place on-the side of the frame bv the central Screw 60.

-Whilethe construction and arrangement of the improved automatic stopmotion mechanism as herein described and claimed, is that of aenerally'preferred form, obviously modi 'ations and changes may be madewithout departing from the spirit of the invention or the scope of theclaims.

Iclaim:.- -lHStopLmotion mechanism, including a starting-and stoppinglever, and electromagnetic means energized to hold the lever in thestarting position with a predetermined force, to withstand vibrations ofa strength equal to said force but not those in excess thereof.

2. Stop motion mechanism. comprising a starting and stopping leversubject to vibrations, electromagnetic means for holding the lever inthe starting position, and an electrical circuit for energizing saidmeans to produce a holding force of a predetermined strength on thelever to counteract vibrations of equal force but not those in excessthereof.

3. Stop motion mechanism, comprising a starting and stopping leversubject to vibration, electro-magnetic means for holding the lever inthe starting position, and a closed electrical circuit furnishingcurrent to said means to hold the lever during vibrations of a strengthequal to that of said means, but not in excess thereof.

4. Stop motion mechanism, comprising a starting and stopping leversubject to vibration, electromagnetic means for holding the lever in thestarting position, a closed electrical circuit furnishing current tosaid means to hold the lever during vibra tions of a strength equal tothat of said means, but not in excess thereof, and associated means forshort-circuiting said electromagnetic means to weaken the hold of thelatter for the release of the lever.

5. In combination with a machine causing vibration in operation, a leverfor starting and stopping the machine, and means to which the leveradheres in the starting posi tion during vibrations of a predeterminednormal strength but which is overcome by vibrations exceeding saidstrength to drop the lever to the stopping position. 7

6. In combination with a machine causing vibration in operation, a leverby which the machine is started and stopped, an electro-magnet in acircuit which remains closed to continuously energize the magnet at acertain strength to hold the lever in the starting position duringnormal vibrations which if exceeded jarsthe lever loose, and electricalcontact means distributed among a plurality of locations throughout themachine, closable by a malfunctioning of machine parts at such locationsto short circuit the electro-magnet for the weakening thereof and therelease of the lever.

7. In combination with an automatic press including sheet feedmechanism, a die, a chute for the product, a scrap chute and a lever forstarting andstopping the press; an electro-magnet continuously ener 'zedat a predetermined strength to hold the liver in the running positionbut being adapted to be jarred loose by vibrations exceeding thestrength of the magnet when the sheet sticks on the die, and electricalcontact means closable to short circuit and weaken the electromagnet forthe dropping of the lever and stopping of the press, upon the feeding inof an extra thick sheet, or the clogging of the product chute or theclogging of the scrap chute respectively.

8. The method of automatically stopping a press, consisting of jarringits starting and stopping lever loose from an energized electromagnetwhile in a running position by vibrations caused by the press andexceeding the strength of the electromagnet.

9. The method of automatically stopping a press, consisting of holdingits starting and stopping lever in a running position by a predeterminedforce, jarring the lever loose to fall to the stopping position, byvibrations of a strength exceeding said force and caused by theoperation otthe press; and diminishing said force for the release of thelever through instrumentalities becoming active upon themail-functioning of parts of the press.

10. In an automatic strip feed press. a starting and stopping lever,continuously energized electro-magnetic means for holding the lever inthe running position, and a contact associated with the feed mechanismand in shunt circuit with said electro-magnetic means, including a stemmoved to close a circuit by a strip of extra thickness, and thusshort-circuit the electro-magnetic means for the release of the lever.

11. In an automatic strip feed press including a starting and stoppinglever, continuously energized electro-magnetic means for holding thelever in the running position, and contact means associated with thefeed prom mechanism and in shunt circuit with said electro-magneticmeans, including a relatively fixed contact point and a relativelymovable'contact point pressed into engagement with the relatively fixedcontact point by the admission of a strip of extra thicknew to close theassociated circuit and short circuit the electromagnetic means for therelease of the lever.

121111 an automatic strip feed press including a starting and stoppinglever, and a discharge chute; a closed circuit embracing andcontinuously energizing electro-magnetic means for holding the lever inthe running position, and insulated contact means in the chute, closinga circuit when the latter becomes clogged to short-circuit theelectro-magnetie means and cause the release of the lever. V

LYMAN LLEWELLYN JONES.

